chapter 13

Question 1

structure of RNA

Answer 1

SUGAR, PHOSPHATE group, nitrogenous base, held together by phosphodiester bonds but has ribose sugar

Question 2

another difference between DNA and RNA

Answer 2

RNA consists of 1 polynucleotide strand
- presence of 2-OH group

Question 2

rRNA

Answer 2

subunit make up the ribosome, the site of protein assembly

Question 3

mRNA

Answer 3

carries the coding instructions for a polypeptide chain from dna to a ribosome

• specifies the sequence of the amino acids in a polypeptide chain and provides a template for joining of those amino acids

Question 4

pre-mRNA

Answer 4

immediate products of transcription

Question 5

tRNA

Answer 5

serve as the link between the coding sequence of nucleotides in an mRNA molecule and the amino acid sequence of a polypeptide chain

• helps incorporate amino acids to polypeptide chain

Question 6

snRNA

Answer 6

combine with small protein subunits to form snRNPS

• some convert pre-mrna into mrna

Question 7

micro RNA

Answer 7

inhibits translation of mRNA

Question 8

small interfering rna

Answer 8

triggers degradation of other rna molecules

Question 9

in prokaryotes Crispir RNA

Answer 9

assist in the destruction of foreign DNA molecules

Question 10

template strand

Answer 10

nucleotide strand used for transcription

Question 11

nontemplate strand

Answer 11

strand that is not transcribed

Question 12

transcription unit

Answer 12

stretch of DNA that encodes an rna molecule

• promotor, RNA coding region, and a terminator

Question 13

promotor

Answer 13

dna sequence that the transcription recognizes and binds
- indicates which dna strand is to be used as the template and direction

Question 14

rna coding region

Answer 14

sequence of dna nucleotides that is copied into an rna moelcule

Question 15

terminator

Answer 15

sequence of nucleotides that signals where transcription is to end

Question 16

ribonucleoside triphosphates

Answer 16

where rna is synthesized from and contains ribose sugar, a base, and three phosphate groups

Question 17

rna polymenerase I

Answer 17

transcribed rna

Question 18

initiation

Answer 18

1. promoter recognition
2. formation of a transcription bubble
3. creation of first bonds between RNTPS
4. escape of transcription apparatus from the promoter

Question 19

cosensus sequence

Answer 19

commonly encountered nucleotides at each site TATAAT